Variable-speed mechanism



Oct. 9 1923. 1,470,563 B. HALL VARIABLE SPEED dMECHANISM Filed May 2l, 1913 5 Sheets-Sheet 1 'llllllllllllllllll/llllllllllllllllllllllllllllllllllnlllllllllh1Illllllllllllllllllllllmwlllllllllllllllllllllllllllllllll/ 35m Q Bw/neazlfazz.

'wffm. y www Oct.`9, 1923. r 1,470,563

l B. HALL 'VARIABLE sfEED MECHANISM Filed May 21, i915 5 sheets-sheet 2 Jjgmf. n

Oct.y 9 1923. 1,470,563

VARIABLE. SP EEEEEEEEEE SM Oct. 9 1923.

B. HALL VARIABLE SPEED MECHANISM Filed May4 2l 1915 5 sheets-sheet 5 Patented Oct. 9, 19u23.

UNITED STATES PATsNro-EFICE.

BICKNELL HALL, or TAUNTON, MASSACHUSETTS, .eissIcrNorv To HALL CO., OF BOSTON, MASSACHUSETTS, A CORPORATION or MASSACHUSETTS.

A VARIABLE-SPEED 'MECHAN'SM Application led May 21, 1913. Serial No. 768,993.

l vTo all whom itmay concer/n.'

Be it known that 1, BICKNELL HALL, a citizen of the United States, and a resident of Taunton, in the county of Bristol and,

State of Massachusetts, have invented an Improvement invariable-'Speed Mechanism, of which the following description, in connection with the accompanying drawings, is a' specification, like characters on the drawings representing like parts. p

This application -is a continuation in part and as to certain common subject matter of my co ending application Seriall No. 507 ,616 filed ul 14, 1909,v renewed as application l5 Serial 0. 204,100 on November 26, 1917 and of which lattermy application Serial No. 240,325 filed June 17, 1918 is a reiling, yand also is a continuation in part and as to certain common subject-matter of my copending application Serial No.'610,295 filed February 23, 1911, renewed'as application Serial No. 157,248 on.y March 24, 1917 and of which latter my application Serial No. 194,012 filed September 29, '1917 is a continuation. 1

This invention relates to variable speed mechanism, an important object thereof being to provide an improved, simplified andl compact construction. The nature of my invention will best appear froma description of a single embodimentthereof selected for illustrative purposes and shown in the,

accompanying drawings, wherein- Fig. 1 is a plan view of a speed varying mechanism embodying my invention, the top of the casing being removed;

Fig. 2 is a verticallongitudinal section of the mechanism shown in Fig. 1;

Fig. 3 is a vertical transverse section upon the line 3 3 of Fig. 2 looking toward. the left in said ligure;

Fig. 4f is a similar view. upon the line 4-4 of Fig. 2 looking toward the right in said fi re gllilig. 5 is a, central horizontal section of the mechanism shown in Fig. 1;

Fig. 6 is a vertical transverse Section upon the `line 6-6 of Fig. 1 looking toward the left in Said figure; I,

Fig. 7 is a similar View upon the line 7-7 of Fig. 1 looking toward the right in said figure;

Fig. 8 is a Vview similar to Fig. 2, but representing the eccentric rings as concentrically positioned with respect to the driving 4shaft; Y v

Fig. -9 isan 'enlargedview in :transverse`l vertical section taken through the driven element, at the right of a median line viewin Fig. 2; 60

ig. 9al is a detail view in vertical section,W of a portion Of the construction. shown in Fig.l 9b is a view similar to Fig. 9 at the left of the median line referred to; A

Fig. 9b is an enlarged view in transverse vertical section taken through4 the opposite driven element from that Shown in Fig. 9;

Fig. 10 is a side elevation of the encased mechanismA and rep-resentin a lmodified form of means for varying t e eccentricity of the rings; y

Fig. 11 is a detail representing in' plan the right hand portion of the speed varying struc-4 ture shown in Fig. 10; .75

Fig. 12 is a longitudinal central sectional view upon the line 12-12 of Fig. 11;

Fi 13 is a transverse sectional view upon the line 13--13 of Fig. 12; and

Fig. 14is a detail showing the connection between the adjusting lever and drive shaft.

Referring iirst to Figs. 1 to 8 inclusive, upon a Suitable base 1, as shown in Figs. 2 and 8, there are erected two end standards 2, 3, which may be integral with or attached to the base and which form a portion of the enclosing casing, the overlying-portion orI top of which is indicated at 4 in said. figures. At'y suitable aligned points in said standards 2, 3 are provided bearings, 6, within which are mounted two end bushings 7, 7 the bushing 7 being positively driven as hereinafter described and the bushing 7 being rotatable through the mechanism interposed between said bushin s and hereinafter described. Mounted within the bushings 7 7 is a driving shaft 8, the rightfhand end whereof, viewing Fig.l 2, projects beyond the casing. Upon said outer end ofthe bushing v 7 is fast a drivingpulleyQ, it being reprewn l sented asv secured thereto by a key of any adjacent to the bushing 7' and the eccentricJv suitable construction. Positioned within the bushing 7 is a feather 11, secured to the bushing by a suitable number'of screws 12, thereby preventing displacement of the bushing upon axial movement of the drive shaft 8. ySimilarly the bushing 7',is provided with a feather 11 secured in position by screws 12'. Thus the driving pulley 9 is keyed to the bushincrr7, and the latter is .i keyed to the driving s aft 8, so that the said thereby of one or more preferably ring-like members capable of adjustment into varyshaft is driven directly by the bushing and indirectly by the said driving pulley 9. This relieves the driving shaft of undue torsional strain. Y

I contemplate the provision 1n connection with the driving shaft and an element driven ing positions of eccentricity, and by adjustment of which any desired variation in speed of the driven member is effected. Preff erably I employ a pair of such members and in this embodiment of the invention have represented the use of a pair thereof, oppo sitely positioned o r balanced upon the driving shaft 8. Within the scope of the invention, however, any suitable number thereof ma be employed.

he said adjustable members, herein` shown as rings are represented at 12A, 12B in the several res, .and are mounted upon or carried by t e eccentrics 13, 13. The lattery are positioned upon the driving shaft and are res ctiveI at the inner ends of the bushings 7 ,7, eac of which latter is provided with an inner head or ange 14 or 14' grooved on its'face as indicated at 14, 14",

as indicated most clearly in Figs. 1 and 2. Each of said eccentrics 13, 13 is provided 'with a pair of ears or projections 15, 15 adapted to enter said grooves, as indicated most olearlyin Fig. l, thereby insuring unitary rotation of said bushings and the said vdriven element, or to ybring the same'into a position of rest. Y y

For this purpose, Ihave hereinA represented `the driving shaft 8 as having a pair' of diametrically o posed key-ways, tapered or wedged shape in longitudinal section. As shown most clearly in 'Fi 2, .3- and 4, that portion of the shaft 8 a jacent to the bushing 7 and: the eccentric 13and receiving the same," in the position of the partey shown -in Figl2, -is provided. with a diamet-v 'ricallyoppos'ed pair of key-ways 16, 17 oppositelyl tapering in lon 'tudinal section and that portion of the said shaft similarly member 13 and receivingV the same, in the position of the arts shown in Fig. 2, is provided with a similar but reversed pair of key-ways 16', 17'.

In each instance, I have represented each key-way as extending at itsV deepest point nearly through the shaft'8, each pair of keyways being separated by a relatively thin web 18, 18'. Within each of the key-waysY is received a wedge or key, indicated at 19, 2() and 19", 20', and each having an inclined inner edge corresponding to the inclination of its key-way. y

Each eccentric 13, 13' is axially recessed to permit its eocentricity to be varied and is provided with two longitudinal key-ways 21, 22, 21', 22'l respectively, of a suiiicient depth to receive the wedges 19,- 20, 19', 20'

respectively, and to permit the radial movement thereof caused by the axial movement of the driving shaft hereinafter described. The form and construction of these features may be widely varied within the scope ofthe invention'.

I provide any suitable means for axially moving the driving shaft 8, thereby to project the wedges 19, 20, 19', .220. For this purpose I have in Figs. 2, `ii'and 8 represented the left hand end of the said drive shaft as axially socketed at 23 for the`reception of the end 24 of a screw 25 mounted in a fixed nut V26 which is itself secured to thev ,casing by a yoke 27 and bolts 28. The outer end of the screw 25 is provided' with a hand wheel 29 fast thereon. The Aend 24 of the screw 25 is seated'for rotation in the socket 23 of the driving` shaft 8, and in order 'to confine the screw in said socket while permitting such rotation, I have herein represented,'as shown most clearly in Figs. 2 and 8, a plate 29'V secured by screws 30 to the end of the shaft 8 and provided with an opening 31 of less size than the diameter ofthe screw 25 and enga-ging a portion thereof lof reduced diameter, as indicated in Fig. 2. For convenience in assembling the parts, the platde 29' may be made in two pieces if desire v wheel`29 when the parts arein r,the position los.'

shown in Fig. 2), will move the said screw f and the driving shaft-8 axially/tol the left, v1ew1ng..Fig. 2, 'Without roigation (j said shaft, and will cause4 the web-s' 18, 18 to,l forceJ the wedges 19,v 20' radially outward and permit the wedges 20, 19' to move radially -inward to acorresponding extent with corresponding change in the eccentricity of the eccentrics 13, 13 The amount of axial movement of the driving shaft 8 determines the extent of radial projection of the wedges 1 19, ,20.',fandtherefore determines the amount of eccentriclty ofY thesaid Veecentrics and consequently the speed vof the driven element.

Axial movement of the driving shaft 8 .in

the opposite direction will force the wedges 20, 19 radiallyoutvvard and permit the corresponding retraction of the wedges 19, 20. In this manner, the eccentrics 13, 13 may be positioned concentrically with the. driving shaft 8 l(as indicated in Fig. 8), thereby bringing the driven element to a position of` For this purpose, l have, in Figs. 2, 3 and4 4,' represented the casing as provided with internal projections 33,33 having sockets wherein are mounted guiding posts 34, 34 receiving thereon sliding sleeves 35, 35. The driving ring 12A is provided with a pair of projecting lugs or ears 36 and the driving ring 12B is provided with a corresponding pair of lugs or ears 36. Loosely passing through said ears 36, 36 are rods 37, 37 the ends whereof are received in suitable sockets in the sleeves 35, 35. Rotation of the eccentrics 13, 13 compels gyratory movement of the driving rings 12A, 12B. Said rings are, however, as stated, held from rotation by the rods 37, 37', upon which the ears 36,. 36 slide, and in Such gyratory movement of the rings 32, 32 the sleeves 35, 35 slide to and fro along the rods 34, 34.

Loosely mounted upon the driving shaft 8 between the eccentrics 13, 13 is the driven element 38 which is here represented as' an annular member or gear having external teeth 39. The' casing is provided with a suitable opening to permit the teeth 39 of the driven element 38 to mesh with any suitable element or part to which motion is to be transmitted, as for example to the pinion 39 upon the shaft 39 shown in Fig. 1,

and having thereon a transmission pulley 39".

The driven element 38 is provided With a hub 40 within which is loosely received the driving shaft 8 and which at its ends abuts against the eccentrics 13, 13 and the driving rings 12A, 12B. The teeth 39' of the driven element 38 are positioned substantially mid-length the hub 40.

At each side of the gear portion proper of the vdriven element 38, the hub 40 is -circumferentially toothed, as indicated at 41, 41, the said teeth constituting worml gears, as most clearly shown in Fig. 9a. These two series of teeth ext-end circumferentially about the hub, and in this embodiment of the invention the teeth are represented as cut orv otherwise suitably formed from the centre of the driving worms hereinafter described and with which they intermesh.

Loosely mounted upon the hub 40 at opposite sides ofthe gear portion thereof, are two sets or series of segments 42A, 42B, 42C

' and 42a, 42", 42c (Figs. 9 and 9b).` Any suitable. number of segments may -be provided in' each-series Vbut in the disclosed embodiment thereof I have represented three segments in each series. These segments are mounted in opposite, annular guide-ways for'med in the driven element 38, such guide ways being constituted -by the hub 40 and the flanges 43, 43 extending from the faces of the driven element 38 as shown most clearly in Fig. 2.

Each of .the gyratory driving rings 12A, 4121, is provided with a series of studs 44, 44 corresponding in number to the segments 42A, 42a, etc., and pivotally mounted upon said studs are la corresponding number of" links 45A, 45B, 45C, and 45a, 45", 45, Shown most clearly in Figs. 6 and 7. The opposite 'ends of said links 45A, 45a, etc., are pivotally connected to a corresponding number of studs 46, 46 upon the segments 42A, 42, etc.

Since the eccentrics or eccentric bearings x 13, 13 and their respective rings 12A and 12B are oppositely disposed upon the shaft 8 it follows that the studs 44 of one seriesy of links lie intermediate the respective studs 44 of the other series, this same arrangement also being true of the studs 46, 46 at the outer ends of said links, and also of the segments themselves.

The described gyratory movement ofthe driving` rings 12A, 12B is transmitted through the, links 45A, 45a, etc., to the segmentsv 42A, 42a, thereby moving them each intermittently and sequentially in opposite directions in curved paths, and in an oscillatory or to and fro manner.

Ilhe driven element 38 is provided with two annular series of internal teeth 47, 47 indicated in Figs. 2 and 8, one series thereof being shown in detail in Fig.. 9. The teeth of the internal gears 47, 47 are inclined at a suitable angle, thus constituting internal worm gears, as indicated in Figs. 8, 9 and 9b, to correspond to theinclination of `the teeth ofthe Worms48A,48B,48C, 48a, 48h, 48,

and with which they mesh as set fort-h. Each of the segment-s 42A, 42a, etc., isprovided v a socket in the forward end of the corresponding segment 42A, etc. In my effort to provide an improved variable speed .transmission Ihave' found that universality of speed adjustment; positive drive-a drive l freefrom heat generating friction; and a reasonably economical and eliicientc'onstruction are greatly' promoted by arranging the the Worm gear intl, cannot compel rotation oi said worm, but on the contrary compels rotation oi the driven element 38 Wherein are formed the worm Lgears el, el. Each main thread 50 is provided with a series oi reiatively short7 that is, small supplemental threads 5l, as shown most clearly in Figs. 9, 9 and 9b. 'lhe pitch of the supplemental threads is greater than the pitch of the main thread 50 and corresponds to the inclination of the internal teeth It?,

t', and is such as to compei rotation of said Worms as hereinafter set forth; that is; the angle of the engaging1 surfaces of said small threads exceeds the angle ci repose.

lihe teeth of the main thread 50 enter hetween the teeth 52 of the gears el, el', as

titl

represented most clearly in Figs. 9, 9b. The

Width and inclination of the main threads 50 is such with relation to the spacing oi the teeth 52 of the gears 4J., Lil that the spi-res or teeth of the said main thread 50 engage one side of Va plurality of said teeth and have clearance at the other side of said teeth, as shown most' clearly in Figs. 9, QD. lin the position of the parte shown in said Figi". 9, and at all times the leading; faces ot the spires or teeth of the main thread 50 engage the rear faces 53, 53 of a series of the .teeth 52,'and there is clearance between the rear faces of said spires or teeth and the leading,T faces lili of said series of teeth 52. The described relation or engagement of the leadingu face of the spires or teeth of the main thread 5G with the rear faces of a series of teeth 52 constitutes the ed'ective driving relation of the said worms with respect to the gears el, el. During this described driving relation oi the Worms 48A, 48a, etc.,with the 'gears el, el, and at f all times the supplemental threads 5i of the' said Worms have clearance with the rear faces of those internal teeth 47, d?" with' which the Worms are in mesh and contact with the leading faces oi" said teeth, as represented in Fig; 9.

When the segments 42A, 42, etc., are moved forward by the driving rings 12A,

l2, in the manner described, the leading faces of the spires or teeth of the thread 5() engage being in engagement with the rear faces of the series of teeth`52, and inasmuch as the pitch of the thread 50 is too steep, that is, small and with the thrust line Within the angle of repose to permit rotation of the Worms, the latter are held from rotation and conseqnently act as drivers to the gears ei.. el.

Thus at each forward movement of each of the' segments, the Worm thereof acts as adriver and imparts rotative mor/'ement to the gears 4l, el as the case maj,T he. Upon the return movement of each segment, ovving to the described clearance, the spires or teeth of the main threads 50 of that segment cease from effective driving engagement with the rear faces of the teeth 52 although remaining in contact or substantially in contact therewith, and the supplemental threads 5l being in engagement with the ieading faces of a series. of the internal teeth di', e?" canse the consequent idle rotation oi' the Worin of that segment, which permits the return of said segment to its former position. This rotation of the Worms is a contracloclrvvise rotation in Fig. 9. rlihus in the forward movement of any segment, its Worm is held from rotation and acts as a driver, and upon the return or inactive movement of each segment, the Worm rotates `freely in a contraclochwise direction, (viewing Fig. 9) hut does not act as a. driver. Vhile each Worm is acting as a driver, it has no rotative movement, and thus ali friction incident to rotation While acting as a driver, is avoided. rThus each worm partakes of the general nature of a ratchet b ut picks up anywhere, so that an intermittent or ratchet movement of any desired extent is thus secured. Furthermore, the action oi' the Worms is noiseless and ab solntely positive. i The large teeth of small pitch oi the worm. and its Worm gear and the small teeth of large pitch and their gear are so proportioned that 'the Worm would turn the driven element 38 at the saine speed if either were driving; in other words, if the large pitch Worm were so designed to make ten turns of the Worm to one oi the gear 38, the small pitch must be designed ten to one it those teeth were driving. Within the scope of my invention 'such mechanism may he employed in substitntion for the scr-'called diderential, employed in automobiles and other mechanisms, being peculiarly1 serviceable for such purpose.

W ith the described construction, it wili be understood that the driven element 38' is constantly driven in thejsame direction at a' speed depending upon the eccentricityof L the eccentric elements ft, which, as previously described, maybe vari` vd Within the limits of the mechanism, thus 'providing'for any speed in thesame direction. inasmuch as theL eccentric elements 13, 13 are oppof v the other being effective to drive.

sitely mounted upon the driving shaft 8 and with the segments and their worms of one set consequently intermediate those of the opposite set, as above described and as is clear from the drawings particularly by comparing Figs. v6 and 7 and Figs. 9 and 9b, it follows that during the return movement of any or all the segments ofl one set of segments, some one segment and worm of the other set of segments is acting as driver, at all times a worm or worms of one set or Therefore, the rotation of the driven element 38 is continuous. By circumferentially shifting the internal gears v47, 47 by means not shown, but which may he applied thereto for manual or other operation, I may effect a change in the direction of rotation of the dri-ven element' 38 without change in the direction of rotation of the driving shaft.

The construction shown in Figs. 1 to 8 inclusive for axially adjusting the driving shaft 8 is'preferred, because of its simplicity,l but the invention is not limited thereto. If the mechanism be mounted overhead, then the hand wheel 29 may be replaced by a sprocket gear carrying a depending sprocket chain, which maybe seized and drawn upon to effectrotation of such sprocket gear and axial adjustment of the shaft 8, thereby varying the speed of the driven' element 38.

Any suitable means may, however, be provided axially to adjustthe driving shaft 8, so as to vary the speed of the driven element, although it will'be understood that within the scope of the invention, the speed of the driven element may be varied in any suitable manner. Y

In Figs. 10 to 14 inclusive, I have' shown one other form of mechanism involving the use of aha-nd lever, thus adapting the mechanism for convenient use with automobiles or the like.

In said figures, the shaft 8 is represented as provided with an extension 55, 'to which a lever 56 is Vconnected by a, Aoke 57 and pin insad lever sb as to allow t e shaft to turn.

i Said lever atits lower end is pivoted 'at 58 site faces of said projection-are provi ed- VI 'lever 56 near' itsupper end, is a link 66,v

to a link 59 itself pivoted at 60 upon a lug 61 projecting from` one .end 3 of the 'casin 4. l

with Vguiding grooves 64, 64, f

Pivotallysecured at 65 to the operating which at its "outer end is. forked,las indicated most clearly in Fig. 11, and is there provided with'bearings 67, 67 within which vis looselymounted thestud shaftv 68 of a pinion `69, the teeth 704 whereof mesh with the teeth 63. of the longitudinal projection 62.

The operating lever 56 is provided with a latch member 71 pivoted to the said lever at 72'and normally outwardly pressed by a v spring 73 shown in Fig. 10. The latch member 7l has nivoted thereto at 74 a socket piece 75 mounted wherein is a rod 76, the forward end of which has a locking tooth 77 adapted to enter between the teeth of the inion 69 and hold the same from rotation. n order to support the forward or outer end of the rod 76, I have herein represented it as provided with an elongated slot 78 through which passes a screw 79 tapped into `a squared portion 80 of the link 66. The

of the pinion 69. This unlocks the pinion 69 and ermitsy it to 'move lrotatively along the projection 62 with the consequent axial movement of the shaft 8 to the desired extent. In order to hold the pinion 69 in its proper relation to the projection 62, I have represented the stud shaft 68 of the pinion 69 as rovided withdepending ears 82 having pins 83 which enter the longitudinal guide grooves 64 of the projection 62. In the device illustrated herein the driving belt is applied to the driving ulley 9 which, with its shaft` 8 and eccentric earmgs 13 and 13 and their rings 12A, 12B, transmit rotary motion to and through the other -parts of the device; hence said driving pulley,its shaft, eccentric bearings and rings may vtogether be considered as the driving element, or any one of them might be so considered. The bearings 13,13', as stated,

are herein driving'elements, being positioned upon'and actuated by and with theshaftl 8 which herein is rotated, and 'the axes of said driving elements are adJustable as to vtheir eccentricity relatively to both nthe drive' shaftv and to the driven eleme 38.

lio

' In the device illustrated, power is taken from 'the' annular member or gear -38 through the. ear teeth 39 which gear and its parts in t e present' form of my invention is the driven element of the device and the 'axes of this driven element and ofthe -vdriving elements 13, 13I heretofore men'-` tioned are relatively adJustable into positions fof greater or less 'eccentricityn Operatively interposed between the drivn ing and driven elements are the groups/of segments and their worms and which serve to transmit motion and power from the driving element to the driven element. Each segment and worm together4 with its linkl which moves it, constitute one form of what may conveniently be termed a driving unit for transmitting motion from the driving to the driven elements. The driving units of each group are herein distributed in a single plane about the axes of the driving and driven elements and are operatively con-.I nected through their links and studs with one of said' elements, herein the driving element, in a crank-like manner, that is to say, as the driving pulley 9 is rotated it causes the axis of the driving elements 13, 13C-thc axis that is adjustable eccentrically-to describe a movement like a crank which furnishes the connection between said drivingl element` and the driving unit or units.' With the eccentric bearings 13, 13' ad' justed into eccentric positions, the outer portions of each driving unit where its worm engages the teeth 52 of the driven element 38, have intermittently effective drivingl engagement with said element and the points of such engagement change or are'adjustable around the. pitch line circle l or circumference -of said element since at each succeeding driving engagement said worm engages a new tooth or teeth more or less removed fromthat or those previously engaged, the points of engagement progressing' around the said driven. element in steps determined as to the period, spacing or` rapidity of engagement according to the exe `tent of relative eccentricityof the axes ,of

the driving and driven elements above mentioned. Thus while the effective driving en- `which it is engaged during the driving period; that is, the thrust line of a driving unit lieswithin the. 'angles of respose iianking a line normal to the face lof said. abutment formation which receives it; 'In the present instance that abutment formation is i the effective face or faces of the worm teeth on the 'driven element, said teeth providing a plurality of engaging faces of limitedV extent with which. the driving units progressively have intermittently effective driving engagement.' Said arrangement, thatjpermits the driving thrust to be thus delivered- "'upoii the abutment face 'of the driven element in a line A'substantially normal to said face and provides-Aan abutting contact be-A tween the driving unit and engaged element, renders the device in effect positive in its action in that it'is free from heat generating conditions that characterize any clutch or gripping arrangement for deliver- 'ing the driving thrust from the driving unit to the driven member in any other than la substantiallyjnormal line with respect to the engagedl member.

If the driving thrust were exerted in direction fnot substantially normal' to the abutment face or formation of the element engaged by it, the moment the angle of repose at either side a line truly normalto that abutting face would be passed, the drivingthrust would tend tovproduce. alateral slipping action between the driving unit and said face, which would' require resistance by some friction clutch or other device.

o long, however, as the driving thrust is vvii;4

inthe `angles'ofgrepose at' either side of line trul normal to the abutmentl face,'said line of t rust maybe said to be'substantially f normal to said face and may beeinplofed as' eliver freelyl as if it were a true rioI mal to positive or direct driving orce from one part to its engaged partwithout liability to lateral slip and without requiring any-supplementary clutches or other devicestol maintain the engagement, in which ysense the :device is positive in its action;

By the provision of worm gearin as herein shown, in the engagement vo the driving units and their engaged element the range of adjustment speed due to relative adjustment of the axes of the driving elements 13, 13 and driven-element into positions of greater or less eccentricity is'rendere'd trul universal, so that any intermediate spee may be obtained from minimum to maximum. For each driving unit there is provided a continuous face, herein the drivling face of the worm, of a- .length to reach from one to another ofthe pointsof intervmittently effective engagement. of thel cooperating face, that is, herein, from one to another tooth of the worm gear. By such an arrangement the driving units may 'have driving contact with said engaged element .at any point circumferentially thereof andy in any relative positions of the axes of the l "driving elements 13, 13 and driven element,

and accordingl the speed obtained isv universallyvariab e by increments of any desired size. This is `due to the capacity of said driving units and their engaged element universally vto be adjusted relatively circum- .ferentially about the axis of saidengaged element throughoutl a complete circle.

As already observed, the points ofengagement of the driving unit rwith the engaged element shift variably` around the vlatter according to the-extent fof said relative eceentricity. p' They'also vary according restrain said rings. from rotation, a driven' to the radial position of the points of connection of the driving units with the driving rings 12A, 12B relative to the axis of the drive shaft and of the driven element. The driving units, it will be noted, are always positively held and guided, herein bythe annu'- lar uideways in the driven element 38.

aving thus described one illustrative embodiment of my invention, I desire it to be understood that althou h specific terms are employed, they are use in a generic and descriptive sense and not for purposes of limitation, the scope of the invention being set forth in the following claims:

1. Variable speed mechanism comprising in combination a drive shaft, a member of variable eccentrcit positioned thereon and moved thereby, a riven element concentric with said shaft and provided with worm gearing, a circumferential series of worms engaging said worm gearing and adapted when oscillated to rotate thesame in one direction, and operating connections between said worms and said member of variable eccentricit whereby rotation of said sha-ft and atten nt eccentric movement of said member causes oscillatory movements of said worms of a length dependent upon the eccentricity of said member.

2. S eed varyin mechanism comprising in com ination, a rive shaft, eccentric elements operatively related thereto, means to vary the eccentricity thereof, gyratory rings `interposed worms and segmentscarryingthe same between said opposed eccentrics and .said driven element.

5. Speed varying mechanism comprising ,in combination, a drive shaft, eccentric'elements 13, 13 thereon, gyratoryrings 12A, 12B, cooperatively related thereto and adapted to be positioned thereby, `means to element 38 having a hub 40 .loose upon said drive shaft, se

42", 42, operatively relatedv to,said gyratorv rings, and worms 48248, 48C and 4 8, 485, Y 48, carried by said segments respectively*V a-ndhaving intermittent drivingr relation to said driven element.

. 6. Variable speed mechanism comprising in combination, a drive shaft, a variable ecl centric upon` and operatively connected thereto', a circumferential series of segments oscillatable by Said eccentric, 'a driven element coaxial with said shaft,'and worm means to transmit motion from said segments to said driven element thereby to rotate the latter in a given direction.`

7. Transmission mechanism comprising in combination, a drive shaft, a driven element concentric therewith and a circumferentialy series of worm drive members between and operatively related to said driving shaft and said driven element.

8. Transmission mechanism comprising in combination, a drive shaft, a driven element mounted concentric thereon, a drive transmission worm therebetween and means con'- trolled by 'said drive shaft to impart to and vfro movement to said drive transmission or -worin Ithereby 'to impart motion to said driven element in one direction.

9.) Transmission mechanism comprising in combination, a drive shaft, a driven element loose thereon, a circumferential series of worms therebetween andoperatively connected thereto,'and means controlled by said ldrive shaft for imparting to and fro movement to said worms.

10. Transmission mechansm comprising in combination, a drive shaft, a driven element concentric therewith, operative connections between said drive shaft and driven element and including a toothed hub and an. internally toothed ring, and one or more worms between and meshing with the teeth of said hub and ring.

11. Transmission mechanism comprising in combination, a drive shaft, a drivenelement concentric therewith, operative connections between said drive shaft and driven element and including a toothed hub and an internally toothed ring, one or more worms between and meshing with the teeth of said hub and ring, 4and means for imparting to and fro movement to said worms. 12. Transmission mechanism comprising in combination, a drive shaft, a driven element loose upon saiddrive shaft, a worm therebetween and operatively connected thereto, means to impart to and fro movement-to said worm, said worm being non-rotative during movement in one direction and being Irotative during movement in the op. posite direction.

13..Transmfssion mechanism comprising in combination, a drive shaft, -a driven ele` ment loose upon sai-d drive shaft, a plurality of worms for transmitting movement to said driven element from said' drive shaft, means controlled by said driveishaft to impart to and -fro movement to said worms, said worms being` non-'rotative during the driving portion their to and fron movement.

14. Speedl varying mechanism comprising in combination, a drive shaft, a driven element coaxial therewith, driving connections between said drive shaft and driven element including worm gearing for said driven element having adriving movement and an opposite idle movement, and variable eccentric vmeans upon said shaft` for imparting said movement to said worm gearing thereby to rotate said driven element.

15. Transmission mechanism comprising in combination, adrive shaft, a'driven ele-l and inner worm gears having teeth adapted to mesh with said worms, and means operaivelyconnected to said drive shaft for imparting to and fro movement to said worms.

17. Transmission mechanism comprising in combination, a drive shaft, a driven element'concentric therewith having outer vand inner worm gears, and a series of segments operatively connected to said drive shaft -and each carrying a worm adapted to mesh with the teeth of said worm gears.

18. Speed varying mechanism comprising in combination, a drive shaft, a driven element 38, cooperating means between said drive shaft and driven element including adjustable eccentrics 13, 13', gyratory rings 12A, 12B on said eccentrics, means controlled by axial adjustmentjofsaid shaft to vary f the adjustment of said eccentrics, segments 42A, 42H42C .and 42, 42, 42c pivotallyconnected to said gyratoryrings, and worms 48A, 48B,- 48C and 48%, 48", 48c carried by said segments' for transmitting movement in one direction to said driven element.

19. Transmission mechanism including a drive shaftv and a driven element, and inter- .mediate devices cooperating therewith and including a worm in the form of a helix, the spires` of which are formed lto present vthreads dierentiated with respect toypone another. A 20. Transmission mechanism includinga drive shaft and a driven element, interposed connecting means including a worm comprising a helix, the spires of whichpresent main4 and supplemental threads.

21. Transmission mechanism comprising a drive shaft, a driven element, and connecting 'means including worms having main threads provided with superficial supplemental threads. l

22. Transmission mechanism comprising --a drive shaft, a drivenelement, and connect-1 l j ing means including worms having main threads provided with superficial supple mental threads, said main and supplemental threads being of different pitch.

23a A worm for transmission mechanism provided with main threads having supplemental threads thereon.

24.' A worm for transmission mechanism provided with main threads having supplemental threads thereon, vsaid main and supplemental threads being of different pitch.

25. A driving device comprising a member having inner and outer worm gears, and

one or moreworms'therebetween and adapted to mesh with both of said gears.

26. A driving device comprising a memy ber having inner and outer worm gears, and one or more worms therebetween having main threads adapted to assume a driving relation withone of said worm gears, and supplemental threads adapted to assume an intermeshing relation with the other worm ear. Y g' 27. Transmission mechanism comprising a Worm gear, a worm having main threads adapted toassume a driving, meshing relation therewith, ,'said worm having sup'plemental threads, anda worm gear with which said supplemental threads mesh to impart rotative movement to said worm.

adapted to assume a driving, meshing relation therewith, said worm having supplemental threads, and a worm gear with Which said supplementall threads mesh to impart rotative movement to said worm, and means to impart to and fro movement to -said worm. 1

29. Transmission mechanism comprising a worm gear, a worm having main threads adapted to assume a driving, meshing relation therewith, said worm having supplemental threads, a worm gear with which v said lsupplemental threads mesh to impart rotative movement to said worm, and means to impartto and fro arcuatev movement to saidv worin.

30. ASpeed transmission mechanism com' prising an element -39 having inner teeth 41 and outer teeth 47, and a plurality of worms f 48A., 483,48C adapted to mesh therewith and provided with threads differentiated with respect to one another.

31. Transmission mechanism comprising a driven element 39'having a hub provided with a worm gear 41 and an internal worm gear 47, and a worm having. threads diier-Y entiated with respect'to one another adapted to mesh respectively'with said worm gears l41 and 47.

32. Driving mechanism `comprising in combination, an oscillator;7 worm compris; ing a helix, the s ires of which present a locking, driving ace and, also a rotating 28. TransmissionV mechanism y comprising a worm gear, a worm having main threads face and a Worm wheel (1o-operating with the locking face.

33. Driving mechanism comprising in combination an oscillatory Worm provided with a locking, driving face and also with a rotating face, a Worm Wheel co-operating with the locking face, and means co-operating- With the rotating face to effect there- With the rotation of the Worm.

34. Driving mechanism comprising in combination, a driving Worm Wheel and an operating Worm therefor, said Worm having a locking driving engagement withl the Worm wheel and alsohaving a Worm face for rotating said vvorm and means co-operating with said rotating Worm face to effect of the other, said contacted face being substantially normal to the line 'of driving thrust of said driving unit thereupon.

36. Variable speed transmission means comprising in combinationrotatable driving and drivenelements; means relatively to adjust the axes of said elements'into positions of greater or less eccentricity; driving units distributed about the axes of said elements, each of said driving units being operatively connected with one of said elements and having universally adjustable, intermittently effective driving engagement With a face of the other of said elements, the thrust line of each driving unit lying Within the angles of repose anking a line normal to said face at the point of driving engagement.

37. ln transmission mechanism, the com-V binatlon of a Worm gean and a co-act1ng,

reciproeable Worm havinga main thread u with 'a driving face the line of thrust of which u on athe engagedgear surface lies within' t e angles of repose'ilanking a line normal to said'surface, said Worm also having a co-eXtensive` thread to engage Saidv gear, the line of thrust of said thread upon its engaged surface lying outside the angles of repose flanking a line normal to said surface.

A' 38. Variable speed transmission Vmea-ns comprising in combination, rotatable driving and driven lelements; means relatively to adjust the axes' of said elementsinto positions of greater or less ecoentricity; a group of driving units\d1stributed about the axes ofv said elements and respectively connected with one of said elements'and having able group of driving units having mental portions and distributed about'the intermittently effective driving engagement with the other, said group of driving units and said engaged element providing, one a plurality of engaging faces of limited extent for progressive, intermittently `efec tive driving engagement with the other, said other providing foreach driving unit a continuous face of a length to reach from one to another of the points of intermittently effective engagement of the cooperating face, the engagement being such that the line of driving thrust is always substantially normal to the engaged faces and Whereby universality of adjustment of said points of normal engagement and of the resultant speed transmission may be had as determined by the relative eccentricity of said axes. A

39. Transmission mechanism for converting constant rotary into variable speed rotary motion, comprising in combination an operatively .associated train of elements including a rotary member, an annular member surrounding the axis thereof, an adjustable group of driving units distributed about the axis ofsaid annular member and operatively engaged with said rotary member, said group of driving units and said annular member providing, one a plurality .of engaging faces of limited extent for progressive, intermittently eHective driving engagement with the other, said other providing for each driving unit a continuous face of a length to reach from one to another of the points of intermittently effective engagement of the cooperating face, and mea-ns' to cause said group of driving units progressively to make intermittently effective engagement with and'about said annular member thereby to produce rotation of one of said members With which they are engaged,said effective engagement` being such that the line of driving thrust is always substantiallv normal to the engaged faces and whereby universality of adjustment of said points of normal engagement and of the resultant speed transmission may be had as determinedv by the adjustment of said group of driving units.

40. Transmission mechanism for'converting constant rotary into variable speed rotary motion, comprising in combination an operatively associated train of elements including a rotary member, an annular member surrounding the anistherepf, an audjustaxes of said members, each such unit having positive crank-like engagement With one lof said members, and means to cause said group! of fdriving' units progressively to ma-ke' intermittently eective direct abutting engagement with the other of said' members and with-the line `of driving thrust substantially normal to the engagedsurface therQOLtherebj to produce rotation 'of' one of said members with. which they are engaged, the` points-of said abutting engagement lbeing universally adjustable circum# 5 erentially about theJ axis of the contacted element.

In testimony'whereof, 'I lhave signed my naine to thsspecicaton, in the presence ALL. 

